The pupils from 10-B class decided in the autumn holiday to go on an excursion to the capital. Knowing the number of boys $n$ and girls $m$, determine how many rooms you need to book in a hotel, if each room has $k$ beds and it is forbidden to settle boys and girls together. \InputFile One line contains three numbers $n, m, k~(n, m, k \le 100)$. \OutputFile Print the number of rooms to book in the hotel.